Drive bushing



' Nov. 15, 1938. D, L. MSCQLLY 2,136,418

DRIVE BUSHING Filed Feb. 15, 1936 2 Sheets-Sheet 1 .//7 Ken for v Patented Nov. 15, 1938 UNITED `DRI-vn RUSHINGl Dennis L. DriscolLLos Angeles, Calif., assigner4 to Lawrence Baash; vLos Angeles., Calif.

`.xpplifmtion Eebruary `15, 1936, yseriall No. 64,7082 s Claims. (C1. 255--2.3)

This .invention relates to well drilling. apparatus and relates'more'particularly'to a 'drive .bushingfor a rotary table. A general object of ythis invention is .to provide a simple, practical and 'improved drillA stem :bushing or kelly bushing vfor ya rotary table. i YIn the rotary method of well'drilling it has been :the general practice to vprovidefa master bushing in therotary table having a tapered -opening for receiving the slips which'grip the `drill pipe, etc. ThisV tapered opening has usu- :allybeen provided with asquare recess in its .upper end for receiving `a square flange on the drive bushing or ykelly bushing `employed to ro- Ltate the drilling string. The' square recess and the'square flange of the typical drive bushing have provided only very limited surfaces for lthe transmission .of `the turning forces."

Another object of Ithis invention is to provide a 'drive bushing orkelly :bushing having extensive substantially vertical surfaces for the transmission of the drivingforces or' turning forces.

Another object of this invention is to provide a drive 'bushing or kelly bushing'having a polygonal exterior for cooperating with 'the polygonal opening ofa master bushing' of the general character 'set forth Aand claimed in my Patent No. 2,(l75,028, granted vMarch 30, '1937.

Another object of this'invention is to provide a drive bushing or kelly bushing that is mainltainedin proper cooperation with the drill stem or kelly through engagement with .the inclined walls of slots in the master bushing;

Another object of this invention iis vto provide a drive bushing or kellybushi'ng having lugs or Wings cooperating with 4slots in .the master bushing which wings present `large surfaces for `receiving the thrusts or turning forces from the master bushing yand also prevent working or play of the kelly bushing in the master bushing.

Another object of this invention .is to provide a kelly bushing of the character mentioned em.` bodying series of rollers for cooperating with the kelly for transmitting the turning forces thereto, which rollers permit the vertical feeding or shifting of the kelly with a minimum of friction.

Another object of this invention is to provide a drive bushing or .kelly bushing of the -charac ter mentioned in which the kelly engaging roll.- ers bear on replaceable, hardenedshims or-plates, thus relieving the kelly bushing of Vpractically all friction and wear.

Another object of the invention is to provide a drive bushing of the characterV mentioned in which the majority of the .kelly engaging rollers or parts are below the upper surface of the rotary table effecting a positive, dependable torque transmission.

Another object of this ,invention is to. provide a kelly bushing of the character 'mentioned vembodying tapered vrollers lor frusto-conical yrollers for :cooperating with a worn `drill ystem or kelly.

Another object of this `invention is to provide La kelly bushing 'of the'character `mentioned that is simpleand inexpensive to manufacture.

The various objectsandfeatures of my invention will `be fully'understood from the following detailed description of' typical preferred forms andV applications of my invention,` 'throughout .whichv description reference vis'made to the accompanying drawings, in which:

vFig; V`1 isa top orplan View of one form of the invention showing it :in operatingpositionfin a master bushing. Fig. l2 is an enlarged fragmentary 'vertical detailed sectional view taken sub# stantiallyas indicated by line 2-2 on`Fig. 1. Fig; 3 'is .an enlarged fragmentary verticalfdetailed `sectional view taken substantially asfindifcated byline v3 3 on'liligl. Fig. :4,is a fragmentary horizontal detailed sectional view taken as indicated by lined-LilV on? Fig. 3.A =`Fig.5'is' atop or plan View showingvthe kellybusliingof the present invention arranged iin" another.L form of master bushing and Fig 6 is acviewsimilar Ito Fig. 4 showing another.embodiment of the invention having alspecific .form of .kelly engaging rollers. L

.The form of the .invention illustrated in Figs. 1 to 4, inclusive, of the drawings, is intended for use inra master A.bushing-vll). The bushing'jl comprises two equal complementaryisections `and is seated inthe opening" I'I vofa 'rotary `table T. A polygonalor square flange" I2 lat the upperend of the master bushing `Ill cooperates with a correspondingly shaped` recessv 13 in the upper portion of the'open'ing'l I Wherebythe bushing Ill is turned with) the tableV T.l rThe :master bushing I0 has .a central opening IlIfor receiving the pipe gripping slips (not shown) and Vfor lreceiving the kelly bushing Yof thisinvention. Th'eopening I4 is' polygonall or .square .in transverse cross section" and `is of Y uniform width or size "throughout its length. This formation ofthe'opening I4 is important as it provides *the lopening `with at vertical Vwalls of large extent. In practice Y'the flat walls of the opening I4. extend between the upper'andlower ends of themaster bushing 'IIL Vertically extendingslots l'are `provided'in the Wallof the openingfl'. lI n the case-illustrated in the drawings .there-vis a" slot' I5 in eachcorner of the y'polygonal opening 14.' "The slots I5 are of uniformv widthfthr'oughout Vtheir length having parallel .vertioal'side `Walls. The bottom walls or inner walls I6 ofthevertical slots I5 are' flat 'and are'inclined downwardly Aand inwardly. Theinclinationtiof the Walls IISk isuniform,as illustrated .inFigs 2.

The improved kelly bushing of the fjpresent invention illustrated inFi'gs. :.12 tov "4', inclusive, of

the drawings, includes, generally, a sectional body I1 for arrangement in the opening I4 of the master bushing I0, and series of rollers I8 carried by the body I 1 to cooperate with the drill stem or kelly K.

The bushing body I1 is shaped to fit the opening I4 of the master bushing I0 and to receive or pass the kelly K. In accordance with the invention the body I-1 is polygonal or square in its general configuration having flat substantially vertical sides I9 for cooperating with flat side walls of the opening I4. In accordance with the invention the bushing body I1 has lugs or wings 20 on its corner portions for cooperating with the slots I5 in the master bushing I0. The wings 20 extend vertically of the body I1 and have parallel substantially vertical sides 2I for cooperating with the side walls of the slots I5, and flat downwardly and inwardly inclined outer surfaces 2 Ia for contacting the inclined slot walls I6. The wings 20 are preferably of substantial length and may extend from adjacent the top of the body I1 to the lower end of the body. The walls of the body I1 and its wings 2D may be hollowed or chambered and reinforcing ribs 22 may extend through their interiors. The upper end of the bushing body I1 is preferably flat and the body I1 is preferably proportioned to project above the upper surface of the master bushing I when the kelly bushing is properly seated in the opening I4. A central vertical opening 23 is provided in the bushing body, I1 to receive the kelly K. Where the drill stem or kelly K is square in transverse cross section as illustrated, the bushing opening 23 is square and'is of uniform size and shape throughout its length. The opening 23 is proportioned to receive the kelly K with suitable slight clearance. The bushing body I1 is preferably sectional to be readily assembled in the opening I4 of the master bushing IIJ. The body I1 comprises two equal complementary sections A and B. 'Ihe plane of division or separation of the body I1 substantially bisects two opposite side walls I4 of the opening 23.

The rollers I8 are provided to engage the drill stem or kelly K to transmit the turning forces thereto and areV such that the kelly K may shift or move vertically through the bushing body I1 with a minimum of friction. The rollers I8 are provided in the interior of the bushing body I1 being arranged in slots 24 in the walls of the opening 23. The slots 24 are vertical and eX- tend downwardly from the upper end of the body I1 to points a short distance from the lower end of the body I1. Each slot 24 carries a series or plurality of rollers I8 and there may be one or more spaced slots 24 in each wall of the polygonal bushing opening 23. It has been found sufiicient and practical to provide one slot 24 in each wall of the polygonal opening 23 adjacent its forward extremity relative to the direction of rotation of the table T whereby the rollers I8 in the slots 24 have the proper driving or turning cooperation with the kelly K. The arrow in Fig.

1 of the drawings indicates the forward or usual direction of rotation of the assembly. The rollers I8 .are arranged in stacks or in superimposed relation in the slots 24. In the form of the invention being described the rollers I8 are cylindrical having cylindrical peripheral surfaces for contacting the sides of the square kelly K. The invention provides hardened replaceable shims or liners 25 on the inner walls of the slots 24. The liners 25 may be formed of spring steel and are easily inserted in and removed from the upper ends of the slots 24. The kelly engaging rollers I8 rotatably bear on the liners 25 and their peripheries project from the walls of the opening 23 sufficiently to have the desired contact with the kelly K.

Vertical opposed grooves 9 are provided in the side Walls of the grooves of the slots 24 to receive trunnions or axles 26 of the rollers I8. The axles 26 are received in the grooves 9 with substantial clearance to permit the proper working of the rollers I8 and to allow for a reasonable amount of Wear. The cooperation of the axles 26 with the walls of the grooves 9 prevents the loss of the rollers I8 from the grooves. 24 during the handling of the kelly bushing. Means is provided for preventing the rollers I8 from jumping or working up out of the slots 24. Plates 29 are arranged on the upper end of the bushing body I1 to cover the upper ends of the slots 24. In practice the plates 29 may be secured to the body I1 by screws 30 or the like. The plates 29 may be substantially U-shaped to extend around the adjacent portions of the opening 23 without interfering with the kelly K. The plates 29 extending over the upper ends of the slots 24-prevent the upward displacement of the rollers I8 from the slots. The uppermost rollers I8 may have substantial clearance with the plates 29 to provide for the proper turning and play of the series of rollers. Tapped openings 3| may be provided in the plates 30 to receive lifting rods or lifting tools to facilitate the handling of the body sections A and B.

The invention provides adjustable means for limiting downward movement of the sections A and B of the bushing body I1 in the opening I4. Ears or lugs 32 project from the bushing body I1 above the upper end of the master bushing I0. In practice a lug 32 may project from the outer end or side of each wing 20. Screws 33 are threaded through openings in the lugs 32 and are adapted to contact the upper surface of the master bushing I0 to limit the downward movement of the bushing I1 in the opening I4. Lock nuts 34 may be threaded on the screws 33 to clamp against the lugs 32 and set or hold the screws 33 in adjusted position. The screws 33 may be adjusted and set to engage the bushing I I! and stop the bushing body I1 in a position where the inclined surfaces 2Ie of the wings 20 have proper cooperation with the inclined walls In the operation of the improved kelly bushing described above the sections A and B of the body I1 are arranged in the opening I4 of the master bushing IIJ to engage about the kelly K. The outer inclined surfaces 2|a of the wings 20 cooperate with the inclined walls I6 of the slots I5 to urge the bushing sections A and B into proper engagement with the kelly K and assist in aligning the bushing in the table T. The rollers I8 cooperate with the flat vertical surfaces of the kelly K for the transmission of the turning forces to the kelly. The iiat walls of the polygonal opening I4 have torque transmitting cooperation with the iiat sides I9 of the body I1 and the side walls of the slots I have similar engagement with the flat sides 2I of the wings 20. As the surfaces I9 and 2I extend throughout substantially the entire length of the body I1 and may be engaged by the walls of the opening I4 and the slots I5 throughout their entire extents the master bushing I0 has extensive driving engagement with the kelly bushing I1. The screws 33 may be set to engage the upper surfaces of the bushing I0 to position the sections A and B Where the inclined surfaces 2Ia of the wings 2l] have proper engagement with the inclined slot walls I6. The polygonal bushing I1 provided with the external Wings 20 fitting the correspondingly shaped opening I4 of the master bushing I0 is positively driven by the master bushing and has such extensive cooperation with the master bushing that it cannot work or wear. The rollers I8 engaging the kelly K positively drive or turn the kelly and being rotatable allow for the free feeding or vertical shifting of the kelly. As the rollers I8 bear on the hard liners 25, the body Il of the bushing is not subjected to wear in driving the kelly. The plates 29 dependably prevent upward displacement of the rollers I8 and yet permit the proper play and movement of the rollers. The rollers I8 may be easily replaced when Worn and the replaceable liners 25 may be replaced from time to time to recondition the kelly bushing.

Fig. 5 of the drawings illustrates another application of the invention. In Fig. 5 of the drawings the body I 'I of the kelly bushing described above is shown arranged in the opening 45 of a master bushing 4I. The kelly bushing comprising the sectional body I'I, the kelly engaging rollers I8, the plates 29, the adjusting screws 33 and the associated parts may be identical with the kelly bushing described above. The opening 40 in the master bushing 4I is of the same shape as the opening I4 and has flat walled slots 42 in its corners for receiving the wings 2E! of the body I'I. The exterior of the master bushing 4I differs in configuration from the exterior of the master bushing I0. The exterior of the bushing 4I is round or cylindrical and an annular outwardly projecting flange 43 is provided on the bushing 4I at its upper end. The flange 43 fits in a recess 44 in the rotary table R to support the bushing 4I in the table. Circumferentially spaced lugs 45 are provided on the ange 43 and cooperate with bayonet slots 46 in thewall of the recess 44 to provide a drive between the table R and the bushing 4I and to hold the bushing in the table. Plates or blocks 41 are inserted in the bayonet slots 46 ahead of the lugs i5 to lock the lugs in proper cooperation with the bayonet slots. The operation of the assembly shown in Fig. 5 of the drawings is identical with the operation of the previously described embodiment of the invention.

Fig. 6 of the drawings illustrates a form of the invention adapted to receive and drive a worn drill stern or kelly S. The drill stem or kelly S is worn so that its side faces 50 which receive the turning forces are no longer at right angles to the adjacent parts of the adjoining faces. In the form of the invention shown in Fig. 6 of the drawings the slots 24a provided in the walls of the kelly bushing opening 23 have vertical inner walls 5I angularly disposed with relation to the side walls of the slots and with relation to the walls of the opening 23. Hard replaceable liners 52 may be inserted in the slots 24a to cover the walls 5I. Series of rollers I8a are provided in the slots 242-. The rollers I82L are tapered or frusto-conical to have proper cooperation with the liners 52 and the worn faces 50 of the kelly S. The tapered rollers I8a project into the opening 23 to transmit the turning forces to the kelly S through their cooperation with the worn faces 50. Axles 54 on the opposite ends of the rollers I 8a cooperate with vertical grooves 9a in the walls of the slots 24a to prevent inward displacement of the rollers from the slots. The kelly bushing shown in Fig. 6 of the drawings may be identical with the previously described form of the invention except for the features just described. The engagement of the frusto-conical rollers l8r with the worn faces 50 of the drill stem or kelly S prevents looseness or excessive play of the kelly S in the opening 23 and accordingly prevents back-lash or slap during operation. The taper or pitch of the surfaces of the rollers I8a may be properly related to the worn surfaces 5I! of the kelly S to provide for the proper engagement between the kelly bushing and the kelly.

Having described only typical preferred forms and applications of my invention I do not wish to be limited or restricted to the specific details herein set forth, but wish to reserve to myself any variations or modifications that may appear to those skilled in the art or fall within the scope of the following claims.

Having described my invention, I claim:

l. In combination, a rotary table bushing having a vertically extending polygonal opening with slots in its corners, and a polygonal drive bushing in the first named bushing having a projecting wing at each corner, said wings cooperating with said slots, the drive bushing having a polygonal opening for receiving a drill stem.

2. A bushing for driving a drill stern comprising, a polygonal body having a polygonal opening for receiving the drill stem, and a wing on each external corner of the body, said wings having inclined outer surfaces.

3. A bushing for driving a drill stem comprising, a polygonal body having an opening for nonrotatably receiving the drill stem, and a projecting wing on each external corner of the body.

4. A bushing for driving a drill stem comprising, a polygonal body having an opening for nonrotatably receiving the drill stem, and a vertically extending wing projecting from each corner of the polygonal body. c

5. A drive bushing for a rotary table compris ing, a polygonal bushing body having a polygonal opening and slots in the walls of the opening, a projecting wing on each external corner of the body, and series of rollers in the slots for contacting a drill stem extending through the opening.

6. A drive bushing for a rotary table comprising, a bushing body having a polygonal opening, and slots in the walls of the opening, series of tapered rollers in the slots for engaging a drill stern extending through the opening, and means for retaining the rollers in the slots.

'7. A drive bushing for a rotary table comprising, a bushing body having a polygonal opening, and a slot in each wall of the opening, the slots in the adjacent walls of the opening being spaced one from the other, series of rollers in the slots for engaging a drill stem extending through the opening, there being longitudinal grooves in the side Walls of the slots, and axles on the rollers cocperable with the walls of the grooves to prevent loss of the rollers.

8. A drive bushing of the character described including, a body having a polygonal opening and longitudinal grooves in the walls of the opening, replaceable shims inserted through the upper ends of the grooves to bear on their inner walls, and rollers in the grooves for cooperating with a drill stem and bearing on the shims.

DENNIS L. DRISCOLL. 

